Consider a window the shape of which is a rectangle of height h surmounted a triangle having a height T that is 1.5 times the width w....

Once you've "considered" the window, what are you supposed to do with it?

I see where you've done some "area" stuff, but that's just geometry. Your subject line refers to "optimization", which is calculus. But what were the instructions? What calculus-type stuff are you supposed to do?